Wireless Internet with a few strings attached

No more toiling next to that modem. You and your computer can roam, once you get past the tricky Wi-Fi setup.

In most homes, the world is crammed into one room -- the one with the Internet modem.

That's where the computer, tied to the modem like a marionette to a puppeteer, gets the Web, e-mail and online music.

But now you can cut the strings.

Wireless networking, popularly known as Wi-Fi, allows you to get an Internet signal anywhere in the house and even out in the yard without a direct connection to the modem.

With a transmitter about the size of a paperback book attached to the modem and a receiver card smaller than a saltine slipped into a laptop, you can e-mail friends while sitting on the sofa, check online recipes in the kitchen, surf the Web in the garden and catch up on the news while lying in bed. And after the initial cost of the equipment, Wi-Fi is free; there are no usage fees above and beyond your basic Internet charges.

Indeed, I am now sitting at my kitchen table with a view of the front garden, which is a nice change from my tiny, almost windowless home office with its depressing mounds of unfiled papers. Yet the Internet is flowing into the laptop at essentially the same speed I get at my wire-bound desktop computer back in the lonely office.

Wi-Fi also provides a handy solution for homes with multiple computers. A wireless connection can simultaneously serve several computers with no speed penalty. And transmitters are for the most part cross-platform, serving Windows and Macintosh computers.

This through-the-air networking has been around for several years, with the vast majority of systems set up by experts for commercial or corporate establishments. Home setups existed, mostly in the abodes of brave experimental types.

But in the last year, wireless has become so much cheaper and easier to install -- a transmitter and receiver can be bought for a total of less than $100 -- that Wi-Fi has crossed the line from nerd-dom to the mainstream.

"There is no reason, anymore, to pay an electrician to run wires all though the house to hook up the computers," says mobile computing analyst Ken Dulany of Gartner Inc. "So many people I know are going Wi-Fi, and there is not one I've talked to who doesn't like it."

Away from home there are benefits too. With a Wi-Fi-equipped laptop, you can take advantage of wireless Internet connections at thousands of public access points already established around the world (although many require usage fees) in coffee shops, hotels, airports and bookstores. Just by walking into one of these areas, you get a speedy connection you can use to e-mail back home or browse the Web.

Drawbacks? A few, which is the norm for an emerging home technology. The Wi-Fi transmitters have a maximum range of about 150 feet under optimal conditions, but those are rare. The signal is diluted by walls and other obstacles, creating dead or near-death signal zones.

Large houses with solid walls (wood or metal walls are especially difficult for Wi-Fi signals to pass through) might require multiple transmitters for full coverage.

Wireless also somewhat increases the chance that a hacker could get into your system. And although setting up home Wi-Fi is a lot easier than it was a couple of years ago, it can still be a highly frustrating experience.

Going Wi-Fi does not mean you can cancel your Internet service provider. "Some people think that with wireless they will somehow be completely freed from wires," says Frank Keeney, a wireless network installer who co-founded the Southern California Wireless Users Group. "You still need that Internet connection coming into the house."

DSL, cable or dial-up service plugs into a modem that is normally wired directly into the computer. But with Wi-Fi, the wire to the computer is replaced by a transmitter called an access point (an unsexy name for a cool item -- clearly, marketing folks were not involved in the naming stage).

There are several name brands of PC access points you can buy, including Linksys, NetGear, Belkin, D-Link and the behemoth known as Intel.

You can find deals that bring the price on an access point down to as low as about $40, but you'll probably pay $75 to $100, especially if you want various extra features.

Apple Computer, which was a pioneer in home wireless, calls its transmitters "base stations." These devices not only have a better name, they are also slicker looking, have cool features and are generally easier to install. But they're Apple, so they are also more expensive, starting at $200.

Now you need receivers for your computers, and in the PC world they're called wireless adapters. Luckily, most computer folks will know what you are talking about if you simply refer to them as wireless cards; check with the computer manufacturer or a technician to see which card fits into your system.